In at least one sense the “American century” is ending much as it had begun: the United States has again become a nation of immigrants, and it is again being transformed in the process. But the diversity of the “new immigration” to the United States over the past three decades differs in many respects from that of the last period of mass immigration in the first three decades of the century. The immigrants themselves differ greatly in their social class and national origins, and so does the American society, polity, and economy that receives them—raising questions about their modes of incorporation, and challenging conventional accounts of assimilation processes that were framed during that previous epoch. The dynamics and future course of their adaptation are open empirical questions—as well as major questions for public policy, since the outcome will shape the future contours of American society. Indeed, as the United States undergoes its most profound demographic transformation in a century; as inexorable processes of globalization, especially international migrations from Asia, Africa, and the Americas, diversify still further the polyethnic composition of its population; and as issues of immigration, race and ethnicity become the subject of heated public debate, the question of incorporation, and its serious study, becomes all the more exigent. The essays in this special issue of Sociological Perspectives tackle that subject from a variety of analytical vantages and innovative approaches, covering a wide range of groups in major areas of immigrant settlement. Several of the papers focus specifically on Los Angeles and New York City, where, remarkably, fully a quarter of the total U.S. immigrant population resides.
